Computer-Assisted Rational Engineering of a Synthetic Metabolic Pathway for Biodegradation of 1,2,3-Trichloropropane

摘要

Background/Objectives. Natural evolution cannot keep up with fast appearance of new man-made pollutants in the environment. The lack of efficient natural enzymes and entire degradation pathways for mineralization of these unnatural contaminants can be addressed by combination of protein and metabolic engineering. A typical example of such pollutant is 1,2,3-trichloropropane (TCP), highly toxic and potentially carcinogenic compound, which persists in the environment due to lack of natural degraders. A synthetic metabolic pathway has been proposed for degradation of TCP to glycerol by the five-step reaction catalysed by haloalkane dehalogenase DhaA from Rhodococcus rhodochrous NCIMB 13064, haloalcohol dehalogenase HheC and epoxide hydrolase EchA from Agrobacterium radiobacter. Low activity of haloalkane dehalogenase with TCP, imbalanced selectivity and accumulation of toxic intermediates were proposed as bottlenecks of the pathway. The objective of this project was to carry out systematic study and optimization of these bottlenecks in the context of complete synthetic pathway.